This Isn't... How I Met Your Mother... It's a XXX Spoof! (2011)

Synopsis

Your mom always looks so prim and proper; people might think we met at a Sunday picnic in the park. But when I met her things were a little nastier. It was a rip-roaring Gang Bang with a roomful of the biggest cocks I'd ever seen, and your mom was taking every one of them, and taking them in every hole, three at a time! And when she was finally done, she was covered in cum! Now, that's really how we met!"